I too think it sounds a bit difficult to manage... either that or it takes away part of what makes roleplaying roleplaying. Character interaction. But, in Begin, Again, people clearly didn't like when I tried to make a chapter that forced them to interact :P I guess those kinds of RPs are more like... just games. Where you play alone against a game master. Like when you're playing against the computer in video games.

But maybe you could put in "events", where all players get teleported or fetched by a greater force or organisation and brought to a place where they have to finish a mission before they can go on with their journey. They could be specially chosen or something.